جستجوی مقالات مرتبط با کلیدواژه "bmcs" در نشریات گروه "مهندسی معدن"

Grate and its specification can significantly affect the performance of ball mills، semi-autogenous grinding (SAG) and fully autogenous grinding (FAG) mills equipped with this type of discharge mechanism. The grate design، open area and grate aperture size affect grinding throughput. In SAG and FAG mills، the inadequate design of discharge grate can lead to inefficiency of comminution device and creation of a slurry pool which practically stops particles'' breakage. In optimization projects، investigation on discharge grate and its effect on grinding process is critical due to particle size classification at mill exit، which necessitate the effect of grate to be considered in process modeling and simulation. In this project، discharge grates of Esfordi and Gol-e-Gohar plant ball mills and their effect on mill performance were investigated in details to make sure that the modeling and simulation and subsequent optimization studies are accurate as much as possible. To study and determine the effect of the discharge grate، samples were collected from mill feed and discharge streams when the circuits were under steady-state operation. After mass balancing، the discharge streams were simulated by BMCS®. Then the observed and simulated PSD of output were compared. The obtained results showed that the grate inside Esfordi ball mill does not affect the particle size distribution of mil output. In Gol-e-Gohar pilot plant ball mill the grate behaves like a fine screen which should be considered in mill mathematical modeling and simulation.

Nowadays, application of rod mill in new comminution circuit designs is almost absolute. Nevertheless, many installed rod mills are still in operation throughout the country and their performance optimization might be of interest to plant engineers. Simulators are specialized tools for circuit design and optimization. Due to the screening effect observed in rod mills, their mathematical modeling is totally different from that of ball mill units. In this study, rod mill was simulated as a new module in BMCS (BMCS-Based Modular Comminution Simulator) environment. Matrix modeling was considered as an established mathematical model of rod mills. Hence, the rod mill module of BMCS was mainly based on this type of rod mill model. The matrix model was constructed using the concept of consecutive stages of breakage. In each stage of breakage, the ore was subjected to selection, breakage and classification processes. The algorithm followed by the rod mill module of BMCS has been presented in this work. The close agreement between the predicted and measured product size distributions proves the validity of the predictions made by rod mill simulation module and the accuracy of model implementation in BMCS.

Simulation techniques are used to evaluate and optimize the mineral processing circuits. In this research, comminution softwares including COMSIM and BMCS and MODSIM were used to simulate the performance of Se-Chahun ball mill circuit. First the samples were taken from the ball mill circuit, in order to determine the size distribution, solid percent and flowrate of the feed and products. Then breakage and selection functions of the ball mills fresh feed samples were determined using BFDS software. Also, the parameters of the breakage function empirical model and Austin selection model were determined. The residence time distribution of the ball mill circuit was measured using salt tracer. Then those parameters of the hydrocyclone models of Plitt and Nagswararao were determined. Finally, the ball mill circuit was simulated using the above-mentioned three softwares. The comparison of the simulation results with the measured data of the plant showed that all the softwares could predict the circuit performance with high accuracy, although the MODSIM was superior.